PT0E-10911

Portable Gas Monitor

GX-8000(TYPE LEL)
Operating Manual(PT0-098)

<Contents>
1
1-1.
1-2.
1-3.
1-4.

Outline of the Product .............................................................................................. 2
Preface .................................................................................................................... 2
Purpose of use ........................................................................................................ 2
Definition of DANGER, WARNING, CAUTION, and NOTE ..................................... 2
Method of confirmation for Standards and Explosion proof specification................. 3

2
2-1.
2-2.
2-3.
2-4.

Important Notices on Safety .................................................................................... 4
Danger cases .......................................................................................................... 4
Warning cases ......................................................................................................... 7
Precautions ............................................................................................................. 8
Safety information ................................................................................................... 10

3
3-1.
3-2.

Product Components ............................................................................................... 11
Main unit and standard accessories ........................................................................ 11
Names and functions for each part .......................................................................... 14

4
4-1.
4-2.
4-3.
4-4.
4-5.
4-6.
4-7.
4-8.
4-9.

How to Use .............................................................................................................. 17
Before using the gas monitor................................................................................... 17
Preparation for start-up ............................................................................................ 17
Basic operating procedures ..................................................................................... 22
How to start the gas monitor .................................................................................... 23
How to detect .......................................................................................................... 25
Modes...................................................................................................................... 28
Air calibration mode ................................................................................................. 29
Display/setting mode ............................................................................................... 31
How to exit............................................................................................................... 35

5
5-1.
5-2.
5-3.

Operations and Functions ....................................................................................... 36
Gas alarm activation ................................................................................................ 36
Fault alarm activation .............................................................................................. 38
Other functions ........................................................................................................ 38

6
6-1.
6-2.
6-3.
6-4.

Maintenance ............................................................................................................ 39
Maintenance intervals and items ............................................................................. 39
Gas calibration method............................................................................................ 40
How to clean............................................................................................................ 41
Parts replacement ................................................................................................... 41

7
7-1.
7-2.
7-3.

Storage and Disposal .............................................................................................. 43
Procedures to store the gas monitor or leave it for a long time ............................... 43
Procedures to use the gas monitor again ................................................................ 43
Disposal of products ................................................................................................ 44

8

Troubleshooting ....................................................................................................... 45

9
9-1.
9-2.

Product Specifications ............................................................................................. 47
List of specifications ................................................................................................ 47
List of accessories ................................................................................................... 49

10

Definition of Terms ................................................................................................... 50-1-

GX-8000

1 Outline of the Product1-1. Preface

1

Outline of the Product1-1. Preface
Thank you for choosing our portable gas monitor GX-8000 (TYPE LEL). Please check that the model
number of the product you purchased is included in the specifications on this manual.
This manual explains how to use the gas monitor and its specifications. It contains information required forusing the gas monitor properly. Not only the first-time users but also the users who have already used the
product must read and understand the operating manual to enhance the knowledge and experience before
using the gas monitor.

1-2. Purpose of use
This product is a gas monitor used to detect combustible gases (%LEL) in the air.
Detection results are not intended to guarantee life or safety in any way.
Check the specifications before use and conduct gas detection properly in accordance with purposes.
In addition to this operating manual, an operating manual for the data logger management program (option)
is available for the gas monitor. Contact RIKEN KEIKI if it is needed.

1-3. Definition of DANGER, WARNING, CAUTION, andNOTE
DANGER

This message indicates that improper handling may cause serious damage on
life, health or assets.

WARNING

This message indicates that improper handling may cause serious damage on
health or assets.

CAUTION

This message indicates that improper handling may cause minor damage on
health or assets.

NOTE

This message indicates advice on handling.

GX-8000-2-

1 Outline of the Product1-4. Method of confirmation for Standards and Explosion proof specification

1-4. Method of confirmation for Standards andExplosion proof specification
This instrument has some specification depends on standard and explosion proof certificate. Pleaseconfirm the detector specification before using. Please refer Declaration of Conformity that is at the end of
this manual if you have CE marking type. You can confirm instrument specification to see name plate as
follows.
Japan Ex certificate

Main unit

Main unit

Ex marking
CE marking
Battery unit

Battery unit

Japan Ex type name plate

ATEX/IECEx, CE marking type name plate-3-

GX-8000

2 Important Notices on Safety

2-1. Danger cases

2

Important Notices on
Safety2-1. Danger cases
DANGER
Nameplate location
Main unit

Battery unit
About explosion-proof of main unit Do not modify or change the circuit or structure, etc.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 The battery unit that can be connected vary according to Explosion-proof approval No. of mainunit.

GX-8000

Model/Explosion-proof approval No.
of main unit

Model/Explosion-proof approval No.
of battery unit that can be connected

GX-8000 / TC19439

BUL-8000(G) / TC19437
BUD-8000(G) / TC19438

GX-8000 / TC21222

BUL-8000(G1) / TC21223
BUD-8000(G1) / TC21224-4-

2 Important Notices on Safety

2-1. Danger cases

DANGER The specifications of main units are as follows:
Pump circuit:
Allowable voltage of 4.95 V, allowable current of 1.12 A, andallowable power of 1138 mW
Combustible gas sensor circuit: Allowable voltage of 4.95 V, allowable current of 0.834 A, andallowable power of 853 mW
Buzzer circuit:
Allowable voltage of 4.95 V, allowable current of 0.431 A, andallowable power of 441 mW
Main circuit:
Allowable voltage of 4.95 V, allowable current of 0.717 A, andallowable power of 733 mW
Backup circuit:
3.0 VDC, 10 µA
Ambient temperature:-20 ºC to +50 ºC
 Explosion-proof grade of main unit is Ex ia ⅡC T4 X.
About explosion-proof of battery unit Do not modify or change the circuit or structure, etc.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 The main unit that can be connected vary according to Explosion-proof approval No. of battery
unit.

Model/Explosion-proof approval No.
of battery unit

Model/Explosion-proof approval No.
of main unit that can be connected

BUL-8000(G) / TC19437
BUD-8000(G) / TC19438

GX-8000 / TC19439

BUL-8000(G1) / TC21223
BUD-8000(G1) / TC21224

GX-8000 / TC21222

 The specifications of lithium ion battery units are as follows:
Pump circuit:
Maximum voltage of 4.25 V, maximum current of 1.12 A, andmaximum power of 901 mW
Combustible gas sensor circuit: Maximum voltage of 4.25 V, maximum current of 0.768 A, andmaximum power of 618 mW
Buzzer circuit:
Maximum voltage of 4.25 V, maximum current of 0.410 A, andmaximum power of 330 mW
Main circuit:
Maximum voltage of 4.25 V, maximum current of 0.653 A, andmaximum power of 526 mW
Battery charging contact:
Allowable current of 250 VAC 50/60Hz
Ambient temperature:-20 ºC to +50 ºC
 Explosion-proof grade of lithium ion battery units are Ex ia ⅡC T4.

 The specifications of dry battery units are as follows:
Pump circuit:

Maximum voltage of 4.95 V, maximum current of 1.12 A, andmaximum power of 1138 mW
Combustible gas sensor circuit: Maximum voltage of 4.95 V, maximum current of 0.834 A, andmaximum power of 853 mW
Buzzer circuit:
Maximum voltage of 4.95 V, maximum current of 0.431 A, andmaximum power of 441 mW
Main circuit:
Maximum voltage of 4.95 V, maximum current of 0.717 A, andmaximum power of 733 mW
Power supply:
4.5 VDC, 250 mA (Type LR6 manufactured by Toshiba, 3 pcs)
Ambient temperature:-20 ºC to +50 ºC
 Explosion-proof grade of dry battery units are Ex ia ⅡC T4.

-5-

GX-8000

2 Important Notices on Safety

2-1. Danger cases

DANGER
About combination
Make sure that the product model on the nameplate and combination of main unit and battery unit
is correct.
Inappropriate combinations of models deviate from the range of explosion-proof certification.
 IP protection class: IP20



About use While conducting measurement in a manhole or confined space, do not lean over or look into the
manhole or closed space. It may lead to dangers because oxygen-deficient air or other gases
may blow out.
 Oxygen-deficient air or other gases may blow out from the gas exhausting outlet. Never inhale
the air or gases.
 High-concentration (more than LEL) gases may blow out. Never use fire near the gas monitor.

GX-8000-6-

2 Important Notices on Safety

2-2. Warning cases

2-2. Warning cases
WARNING
Sampling point pressure The gas monitor is designed to draw gases around it under the atmospheric pressure. If
excessive pressure is applied to the gas inlet and outlet (GAS IN, GAS OUT) of the gas monitor,
detected gases may be leaked from its inside, thus leading to dangers. Be sure that excessive
pressure is not applied to the gas monitor while used.
 Do not connect the gas sampling hose directly to a location with a pressure higher than theatmospheric pressure. The internal piping system may be damaged.
Fresh air adjustment in atmosphere
When the fresh air adjustment is performed in the atmosphere, check the atmosphere for freshness
before beginning the adjustment. If other gases exist, the adjustment cannot be performed properly,
thus leading to dangers when the gas leaks.
Response to gas alarm
Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based onyour judgment.
Battery level check Before use, check that there remains sufficient battery power. When the gas monitor is used forthe first time or is not used for a long period, the batteries may be exhausted. Either fully charge
the batteries or replace them with new ones before use.
 If a low battery voltage alarm occurs, gas detection cannot be conducted. If the alarm occurs
during use, turn off the power and promptly charge the batteries in a non-hazardous area.
Others Do not throw the gas monitor into fire.
 Do not wash the gas monitor in a washing machine or ultrasonic cleaner.
 Do not block the buzzer sound opening. No alarm sound can be heard.
 Do not remove the battery unit while the power is ON.

-7-

GX-8000

2 Important Notices on Safety

2-3. Precautions

2-3. Precautions
CAUTION
Do not use the gas monitor where it is exposed to oil, chemicals, etc. Do not submerge the gas
monitor under water on purpose.
 Do not use in a place where the gas monitor is exposed to liquids such as oil and chemicals.
 The gas monitor, being compliant to IP67, is not water-pressure-resistant. Do not use the gas
monitor where a high water pressure is applied to it (under a faucet, shower, etc.) or submerge it
under water for a long time. The gas monitor is water-proof only in fresh water and runningwater, and not in hot water, salt water, detergent, chemicals, human sweat, etc.
 The gas inlet and outlet are not water-proof. Be careful not to let water such as rainwater get into
these parts. Because this may cause trouble and gas cannot be detected.
 Do not place the gas monitor where water or dirt gets accumulated. The gas monitor placed atsuch a location may malfunction due to water or dirt that gets into the buzzer opening, gas inlet,etc.
 Note that drawing in dirty water, dust, metallic powder, etc. will significantly deteriorate thesensor sensitivities. Be careful when the gas monitor is used in an environment where theseelements exist.
Do not use the gas monitor in a place where the temperature drops below -20 ºC or rises over 50 ºC.
 The operating temperature of the gas monitor is -20 ºC to 50 ºC. Do not use the gas monitor at
higher temperatures, humidities, and pressures or at lower temperatures than the operating
range.
 Avoid long-term use of the gas monitor in a place where it is exposed to direct sunlight.
 Do not store the gas monitor in a sun-heated car.
Observe the operating restrictions to prevent condensation inside the gas monitor or gas sampling
hose.
Condensation formed inside the gas monitor or gas sampling hose causes clogging or gas
adsorption, which may disturb accurate gas detection. Thus, condensation must be avoided. In
addition to the operating environment, carefully monitor the temperature/humidity of the sampling
point to prevent condensation inside the gas monitor or gas sampling hose. Please observe theoperating restrictions.
Do not use a transceiver near the gas monitor.
 Radio wave from a transceiver near the gas monitor may disturb readings. If a transceiver isused, it must be used in a place where it disturbs nothing.
 Do not use the gas monitor near a device that emits strong electromagnetic waves(high-frequency or high-voltage devices).
Verify that the pump driving indicator is rotating before using the gas monitor.
If the pump driving indicator is not rotating, gas detection cannot be performed properly. Check
whether the flow rate is lost.
Do not forget to perform a regular maintenance.
Since this is a safety unit, a regular maintenance must be performed to ensure safety. Continuing to
use the gas monitor without performing a maintenance will compromise the sensitivity of the sensor,
thus resulting in inaccurate gas detection.

GX-8000-8-

2 Important Notices on Safety

2-3. Precautions

CAUTION
Others Pressing buttons unnecessarily may change the settings, preventing alarms from activatingcorrectly. Operate the gas monitor using only the procedures described in this operating manual.
 Do not drop or give shock to the gas monitor. The water-proof and explosion-proof properties
and accuracy may be deteriorated.
 Do not use the gas monitor while charging it.
 The gas monitor is designed to detect combustible gases, however, the measurement
environment may include gases that have harmful effects on the sensors of this unit.
The gas monitor cannot be used in the presence of the following gases:(1) Sulfides (such as H2S and SO2) continuously existing in high concentrations(2) Halogen gases (such as chloride compounds and chlorofluorocarbons)(3) Silicone (Si compounds)
Do not use the gas monitor in the presence of the above gases (such as high-concentration
sulfides, halogen gases, and silicone), which may shorten the sensor life significantly or cause
malfunctions such as inaccurate readings.
In case the gas monitor is used for detection in the presence of silicone, etc., be sure to checkthe gas sensitivities before using it again.

-9-

GX-8000

2 Important Notices on Safety

2-4. Safety information

2-4. Safety information
Observe the followings to maintain an explosion-proof system.

<ATEX/IECEx specification>

・The Portable Gas Monitor Model GX-8000 is a gas monitor used to detect combustible gases(%LEL) in the
air in hazardous environments.
・The gas sample is sucked in by build-in micro pump.
・The battery can be selected either Li-ion battery or alkaline dry battery.
Li-ion battery unit is called BUL-8000 and alkaline dry battery unit is called BUD-8000.
・The battery unit can be changed even by the end users.

Specification for safety
・Ex ia ⅡC T4 Ga (without NC-6215) ・Ex ia ⅡB T4 Ga (with NC-6215)
・
Ⅱ 1 G Ex ia ⅡC T4 Ga (without NC-6215)
・
Ⅱ 1 G Ex ia ⅡB T4 Ga (with NC-6215)
・Ambient temperature range for use ： -20 ºC to +50 ºC・Ambient temperature range during battery charging ： 0 ºC to +40 ºC

Electrical data
・Power supply of Li-ion battery unit : BUL-8000(G),BUL-8000(G1)
Two parallel connected Li-ion cells used in battery pack BP-8000,BP-8000(1) are from type
Maxell INR18650PB1. Um = 250 V.
・Power supply of alkaline battery unit : BUD-8000(G),BUD-8000(G1)Powered by three series connected Alkaline AA batteries, type LR6 manufactured by Toshiba.
・Backup battery type CR1220 manufactured by Maxell.

Certificate numbers
・IECEx Certificate number ：IECEx KEM 10.0038
・ATEX Certificate number ：KEMA 10ATEX 0085

List of standards
・IEC 60079-0：2017
・IEC 60079-11：2011

・EN IEC 60079-0:2018
・EN60079-11:2012

WARNING・Do not charge in hazardous location.
・Do not charge it expect by genuine charger.
・Do not replace battery unit in hazardous location.
・Do not replace dry batteries in hazardous location.
・Do not attempt to disassemble or alter the instrument.
・Use only battery unit type BUD-8000 with three series connected Alkaline
AA batteries, type LR6 manufactured by Toshiba, or use chargeable battery unit
type BUL-8000(G),BUD-8000(G1).

INST. No. 0 0 0 0 0 0 0 0 0 0 0
AB C
DE
A: Manufacturing year (0-9)
B: Manufacturing month (1-9,XYZ for Oct.-Dec.)
C: Manufacturing lot
D: Serial number
E: Code of factory

Additional information

The performance of the Portable Gas Monitor GX-8000, as a safety device, is not covered bythis certificate.
2-7-6 Azusawa, Itabashi-ku, Tokyo, 174-8744, JapanPhone: +81-3-3966-1113
Fax: +81-3-3558-9110
E-mail: intdept@rikenkeiki.co.jp
Web site: https://www.rikenkeiki.co.jp/english/

GX-8000- 10 -

3 Product Components

3-1. Main unit and standard accessories

3

Product Components
3-1. Main unit and standard accessories
After opening the package, check the main unit and accessories.
If anything in the following list is not included, contact RIKEN KEIKI.
<Main Unit>
GX-8000
main unit<Standard Accessories>• AA alkaline battery: 3• Gas sampling probe
and gas sampling hose: 1

Dry battery unit•

Shoulder strap: 1••

Operating manual
Product warranty

DANGER
About explosion-proof of main unit Do not modify or change the circuit or structure, etc.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 The battery unit that can be connected vary according to Explosion-proof approval No. of mainunit.

Model/Explosion-proof approval No.
of main unit

Model/Explosion-proof approval No.
of battery unit that can be connected

GX-8000 / TC19439

BUL-8000(G) / TC19437
BUD-8000(G) / TC19438

GX-8000 / TC21222

BUL-8000(G1) / TC21223
BUD-8000(G1) / TC21224- 11 -

GX-8000

3 Product Components

3-1. Main unit and standard accessories

DANGER The specifications of main units are as follows:
Pump circuit:
Allowable voltage of 4.95 V, allowable current of 1.12 A, andallowable power of 1138 mW
Combustible gas sensor circuit: Allowable voltage of 4.95 V, allowable current of 0.834 A, andallowable power of 853 mW
Buzzer circuit:
Allowable voltage of 4.95 V, allowable current of 0.431 A, andallowable power of 441 mW
Main circuit:
Allowable voltage of 4.95 V, allowable current of 0.717 A, andallowable power of 733 mW
Backup circuit:
3.0 VDC, 10 µA
Ambient temperature:-20 ºC to +50 ºC
 Explosion-proof grade of main units are Ex ia ⅡC T4 X.
About explosion-proof of battery unit Do not modify or change the circuit or structure, etc.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 The main unit that can be connected vary according to Explosion-proof approval No. of battery
unit.

Model/Explosion-proof approval No.
of battery unit

Model/Explosion-proof approval No.
of main unit that can be connected

BUL-8000(G) / TC19437
BUD-8000(G) / TC19438

GX-8000 / TC19439

BUL-8000(G1) / TC21223
BUD-8000(G1) / TC21224

GX-8000 / TC21222

 The specifications of lithium ion battery units are as follows:
Pump circuit:
Maximum voltage of 4.25 V, maximum current of 1.12 A, andmaximum power of 901 mW
Combustible gas sensor circuit: Maximum voltage of 4.25 V, maximum current of 0.768 A, andmaximum power of 618 mW
Buzzer circuit:
Maximum voltage of 4.25 V, maximum current of 0.410 A, andmaximum power of 330 mW
Main circuit:
Maximum voltage of 4.25 V, maximum current of 0.653 A, andmaximum power of 526 mW
Battery charging contact:
Allowable current of 250 VAC 50/60 Hz
Ambient temperature:-20 ºC to +50 ºC
 Explosion-proof grade of lithium ion battery units are Ex ia ⅡC T4.

 The specifications of dry battery units are as follows:
Pump circuit:

Maximum voltage of 4.95 V, maximum current of 1.12 A, andmaximum power of 1138 mW
Combustible gas sensor circuit: Maximum voltage of 4.95 V, maximum current of 0.834 A, andmaximum power of 853 mW
Buzzer circuit:
Maximum voltage of 4.95 V, maximum current of 0.431 A, andmaximum power of 441 mW
Main circuit:
Maximum voltage of 4.95 V, maximum current of 0.717 A, andmaximum power of 733 mW
Power supply:
4.5 VDC, 250 mA (Type LR6 manufactured by Toshiba, 3 pcs)
Ambient temperature:-20 ºC to +50 ºC
 Explosion-proof grade of dry battery units are Ex ia ⅡC T4.

GX-8000- 12 -

3 Product Components

3-1. Main unit and standard accessories

DANGER
About combination
Make sure that the product model on the nameplate, and combination of main unit and battery unit
is correct.
Inappropriate combinations of models deviate from the range of explosion-proof certification.
 IP protection class: IP20



NOTE

Check the model of the battery unit with the nameplateaffixed to the unit.
A nameplate indicating a compatible model is affixed
to the battery unit to avoid using the gas monitor in
combination with a wrong unit.
Check this information and use a correct combination.
(Top view of battery unit)

Nameplate(Side view of battery unit)- 13 -

GX-8000

3 Product Components

3-2. Names and functions for each part3-2. Names and functions for each part
<Outline Drawing>

GX-8000- 14 -

3 Product Components
(1)
(2)
(3)
(4)

LCD display
Buzzer sound opening
Alarm LED arrays
Infrared communication port(5) ▲/AIR switch(6) ▼/RESET switch(7) DISPLAY switch(8) POWER/ENTER switch(9) Gas inlet(10) Gas outlet(11) Battery cover(12) Battery cover fixing screw(13) Sensor cover(14) Battery unit screws

3-2. Names and functions for each part
Display gas concentrations, alarms, etc.
Emit a buzzer sound at an alarm. (Do not block it.)
The lamp blinks in response to an alarm.
Used to carry out data communications with a PC in data logger
mode.
Keep this switch pressed to perform fresh air adjustment.
When an alarm occurs, press this switch to reset the alarm.
Press this switch to change between display modes.
Turn on and off the power.
Connect a sampling hose to this port.
Exhaust the gas drawn into the gas monitor. (Do not block it.)
Open or close this cover to replace batteries. Must be closed while
the gas monitor is in use.
Fix the battery cover.
There is a sensor inside. May be opened only when the sensor is tobe replaced.
Turn these screws to detach and replace the dry battery pack.

CAUTION Do not jab the buzzer opening with a sharp-pointed item. The unit may malfunction or getdamaged, allowing water or foreign substance, etc. to get inside.
 Do not remove the panel sheet on the display. The water-proof and dust-proof performances will
be deteriorated.
 Do not affix a label on the infrared port. Infrared communications can no longer be conducted.

- 15 -

GX-8000

3 Product Components

3-2. Names and functions for each part

<LCD Display>(4) Pump driving
indicator(1) Pilot indicator(2) Combustible gas
concentration digitaland bar display

(1)
(2)
(3)
(4)
(5)

(3) Battery level icon

(5) Clock display

Pilot indicator
Combustible gas
concentration
digital and bar display

Displays the operating status in the detection mode. Normal: Blinking

Battery level icon
Pump driving indicator
Clock display

Displays the gas concentration as a numeric value and a level in the bar
graph.
Displays the battery level. See the information below for the meanings ofbattery level icons.
Displays the suction status in the detection mode. Normal: Rotating
Displays the current time.

NOTE
The meanings of battery level icons are as follows:: Sufficient /: Low /: Needs charging
If the battery level is lower than the above, the inside of the battery icon starts to blink (GX-8000- 16 -).

4 How to Use

4-1. Before using the gas monitor

4

How to Use
4-1. Before using the gas monitor
Not only the first-time users but also the users who have already used the product must follow the operating
precautions.
Ignoring the precautions may damage the gas monitor, resulting in inaccurate gas detection.

4-2. Preparation for start-up
Before starting gas detection, read and understand the following precautions. Ignoring these precautions
may prevent correct gas detection.
Check that the battery level is sufficient.
Check that there is no bend or hole in the gas sampling hose.
Check that the filter in the gas sampling probe is free of dust or clogging.
Check that the gas monitor, gas sampling probe, and gas sampling hose are connected properly.

- 17 -

GX-8000

4 How to Use

4-2. Preparation for start-up<Attaching Batteries>
When the gas monitor is used for the first time, or when the battery level is low, attach new AA alkaline
batteries.

CAUTION<Replacement> Turn off the power of the gas monitor before replacing the batteries.
 Replace the batteries in a non-hazardous area.
 Replace all of the three batteries with new ones at one time.
 Pay attention to the polarities of the batteries.
 If the battery cover fixing screw is not completely tightened, the dry batteries may drop off orwater may get in through the clearance. Water may also get in if a minute foreign substance iscaught beneath the battery unit.
<Batteries> Use AA alkaline batteries.
Chargeable batteries cannot be used.
(1) Using a flathead screwdriver or coin, turn thebattery cover fixing screw counterclockwise toopen the battery cover.

(2) Paying attention to the polarities of batteries,
replace all the three batteries with new ones.
(3) Close the battery cover and tighten the battery
cover fixing screw.

GX-8000- 18 -

4 How to Use

4-2. Preparation for start-up<Charging Batteries>(when the optional unit BUL-8000(G), BUL-8000(G1) are used)
When the gas monitor is used for the first time, or when the battery level is low, be sure to use theaccessory AC powered charger to charge the batteries.






CAUTION

Use the dedicated AC powered charger.
Charge the batteries in a non-hazardous area.
Charge the batteries at ambient temperatures between 0 - 40 ºC.
Do not use the gas monitor while charging it. Correct measurements cannot be obtained.
Furthermore, the batteries get deteriorated more quickly and may have shorter life.
 The AC powered charger is not water-proof or dust-proof. Do not charge the batteries while thegas monitor is wet.
 The AC powered charger is not explosion-proof.
(1) Open the charging jack cover of the gas monitor.

CAUTION
Do not pull the charging jack cover too hard. It
may get damaged.

(2) Put the plug of the AC powered charger into thecharging jack of the gas monitor.
(3) Connect the AC powered charger to the wall
electric outlet.
When charging is started, the charging indicator
lamp lights up (red).
(Charging time: Three hours at the maximum until
the batteries are fully charged)(4) When charging is completed, the charging indicator lamp goes off.
(5) When charging is completed, disconnect the AC powered charger from the wall electric outlet.
(6) Pull out the AC powered charger plug from the power jack of the gas monitor and reattach the charging
jack cover. Put the charging jack cover as far as it will go.

CAUTION Do not use the gas monitor with the charging jack cover detached. Dust or water may get into thegas monitor, causing it to malfunction. Replace the charging jack cover if it is damaged.
 If the charging jack cover is not completely closed, water may get in from the power jack. The
same thing occurs if a minute foreign substance is caught beneath the cover.
 Disconnect the AC powered charger from the wall electric outlet while it is not in use.

NOTE

 During charging, the battery pack may get hot, but this is not abnormal.
 The temperature of the gas monitor is high immediately after charging is completed. Let it leave for 10
minutes or more before using it. Otherwise, correct measurements may not be obtained.
 When fully charged batteries are charged again, the charging indicator lamp does not go on.

- 19 -

GX-8000

4 How to Use

4-2. Preparation for start-up<Detaching Battery Unit>(1) Loosen the two battery unit screws.
(They need not be completely detached.)(2) Detach the battery unit.
(3) Attach a new battery unit.

NOTE
Make sure that the battery unit is installed in correct orientation bychecking the locations of the connection terminal and projection
portions.
Battery unit screws(4) Securely tighten the two battery unit screws.

CAUTION Turn off the power of the gas monitor before replacing thebattery unit.
 Attach or remove the battery unit in a non-hazardous area.
 If the battery unit screw is not completely tightened, thebattery unit may drop off or water may get in through theclearance. Water may also get in if a minute foreign
substance is caught beneath the battery unit.
 Do not damage the rubber seal.
 To maintain the water-proof and dust-proof performances,
it is recommended to replace the rubber seal every two
years, whether or not it has an abnormality.

GX-8000- 20 -

Bottom of Gas Monitor

4 How to Use

4-2. Preparation for start-up<Connection of Gas Sampling Probe and Gas Sampling Hose> Attach the gas sampling probe to the end of the gas sampling hose.
 Connect the sampling hose securely to the gas inlet (GAS IN) of the gas monitor.

Insert the sampling hose to the gas inlet (GAS IN) until it clicks into
place to ensure connection.

CAUTION Use only a gas sampling hose specified by RIKEN KEIKI.
 Use the gas monitor with the gas sampling probe connected so that no foreign substance isdrawn into it.
 Connect a gas sampling probe and a gas sampling hose by fastening them manually without
using any tool. If they are fastened too tightly using a tool, the plastic part of the gas samplingprobe may be broken.

- 21 -

GX-8000

4 How to Use

4-3. Basic operating procedures

4-3. Basic operating procedures
Normally, the detection mode is used for normal operations. (The detection mode is activated after the
power is turned on.)<<Detection Mode>>

RESET

AIR (long pressing)<<Gas Alarm Status>>(Self-latching <Reset after
Recovery to Normal Status>)<<Air Calibration Mode>>

DISPLAY<<Fault Alarm Status>>(Self-latching)

GX-8000<<Display and Setting Mode>>- 22 -

4 How to Use

4-4. How to start the gas monitor

4-4. How to start the gas monitor<<Start-up Procedure>>(About 30 seconds)
Keep the POWER switch pressed for three seconds or more.

↓
LCD
Alarm lamp lights up.
Buzzer sounds once. (Beep)

All LCDs Light Up.

↓
Date/Time Display↓
Battery Voltage Display↓
Gas Name Display↓
Full Scale Display↓
First Alarm Setpoint Display↓
Second Alarm Setpoint Display- 23 -

GX-8000

4 How to Use

4-4. How to start the gas monitor↓
ID Display↓
Buzzer sounds twice. (Beep, beep)

Detection Mode

CAUTION
After start-up, perform air calibration before performing gas detection (air calibration mode).

NOTE A sensor abnormality alarm is issued before the detection mode is entered if there is any abnormality
in the sensor. Promptly contact RIKEN KEIKI. Gases cannot be detected if there is any abnormality inthe sensor.
 If there is an abnormality in the built-in clock, a fault alarm [FAIL CLOCK] may be issued. Press the
RESET switch. The fault alarm is temporarily reset, and measurement is started with incorrect clocktime.

GX-8000- 24 -

4 How to Use

4-5. How to detect

4-5. How to detect
In the detection mode, put the gas sampling probe close to the detection area and take the reading on thedisplay.
Display example<- Display example
CH4 concentration: 0 %LEL
Time:
13:58
Battery level:
Sufficient

DANGER While conducting measurement in a manhole or confined space, do not lean over or look into the
manhole or closed space. It may lead to dangers because oxygen-deficient air or other gases
may blow out.
 Oxygen-deficient air or other gases may blow out from the gas exhausting outlet. Never inhale
the air or gases.
 High-concentration (more than LEL) gases may blow out. Never use fire near the gas monitor.

WARNING The gas monitor is designed to draw gases around it under the atmospheric pressure. If
excessive pressure is applied to the gas inlet and outlet (GAS IN, GAS OUT) of the gas monitor,
detected gases may be leaked from its inside, thus leading to dangers. Be sure that excessive
pressure is not applied to the gas monitor while used.
 Do not connect the sampling hose directly to a location with a pressure higher than theatmospheric pressure. The internal piping system may be damaged.
 When the fresh air adjustment is performed in the atmosphere, check the atmosphere forfreshness before beginning the adjustment. If other gases exist, the adjustment cannot be
performed properly, thus leading to dangers when the gas leaks.
 Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based onyour judgment.
 Before use, check that there remains sufficient battery power. When the gas monitor is used forthe first time or is not used for a long period, the batteries may be exhausted. Either fully charge
the batteries or replace them with new ones before use.
 If a low battery alarm occurs, gas detection cannot be conducted. If the alarm occurs during use,turn off the power and promptly charge the batteries in a non-hazardous area.
 Do not block the buzzer sound opening. No alarm sound can be heard.

- 25 -

GX-8000

4 How to Use

4-5. How to detect

CAUTION Before performing gas detection, attach the gas sampling probe provided with the gas monitor toprevent disturbances by air dust.
 An oxygen concentration higher than a certain level is required for the gas monitor to correctly
detect gases and display concentrations.
 Long-time detection of a high-concentration combustible gas may adversely influence thesensor.
 Use the gas monitor with the LCD display facing upward. The gas monitor, when used with the
LCD display in a tilted or flat status, may not display correct values.

NOTE

 In a low-temperature environment, the operating time is shortened due to the battery performance
property.
 At a low temperature, the response of the LCD display may get slow down.
 If a combustible gas with a higher concentration than %LEL is drawn, some gas may remain in the gas
sampling hose due to adsorption in the hose, gas sampling probe, etc. After drawing ahigh-concentration combustible gas, clean the gas monitor to remove the adsorbed gas (draw fresh air
and check that the reading becomes zero).
Performing fresh air adjustment before cleaning it completely will result in inaccurate adjustment,
giving adverse influence on measurement. In such a case, remove the gas sampling hose before
performing fresh air adjustment to avoid inaccurate adjustment.

GX-8000- 26 -

4 How to Use

4-5. How to detect<Manual Memory>
Any instantaneous value during measurement can be recorded.
Up to 256 points of data can be recorded. When the number of recorded data points reaches the maximum,
recorded data will be overwritten, starting from the oldest data.
(1) In the detection mode, keep the ▼/RESET switch pressed and press the ▲/AIR switch to prepare forrecording (about one second). The following screens are displayed in turn on the gas monitor.

NOTE
The screen displays the memory number, date, and instantaneous value in turn. Go to the next step toexecute recording. No value is recorded at this point yet. If you do not want to record a value, press the
DISPLAY switch to return to the detection mode.
(2) Press the ENTER switch. The date and the instantaneous value at the time when the ENTER switch ispressed are recorded.
(3) When [END] is displayed, the recording is completed.

Returns to the detection mode.

- 27 -

GX-8000

4 How to Use

4-6. Modes

4-6. Modes
Details on each mode are provided as follows.
Mode
Item
LCD display
Detection―
Concentration display
Mode

Details
Normal state

Air Calibration
Mode―[Air CAL]

Perform the zero adjustment.

Display andSetting ModePeak Display[PEAK]

Display the maximum concentration
detected during measurement frompower-on to the present.

GX-8000

Alarm Setpoint [ALARM-P]
Display
Alarm Test

Display the full scale and alarm setpointvalues and check the alarm operations forthe settings displayed.

Pump
ON/OFF
Setting[PUMP OFF]

Used to turn on/off the pump operations.

ID Setting[ID SELECT]

Display an ID if it has been set in advance.
Also used to change or set an ID.

Log Data
Display[REC.DATA]

Display data recorded to the manual
memory.

- 28 -

4 How to Use

4-7. Air calibration mode

4-7. Air calibration mode
Press the AIR switch.

Keep pressing the AIR switch.
Changes the display to [Adj
HOLD AIR].

When [RELEASE] isdisplayed, release the AIR
switch.

When the zero adjustment is
successfully completed, it
returns to the detection mode.

WARNING
When air calibration is performed in the atmosphere, check the atmosphere for freshness before
beginning the calibration. If other gases exist, the adjustment cannot be performed properly, thus
leading to dangers when the gas leaks.

CAUTION Perform air calibration under pressure and temperature/humidity conditions close to those in theoperating environment and in fresh air.
 Perform air calibration after the reading is stabilized.
 If there is a sudden temperature change of 15 ºC or more between the storage and operation
locations, turn on the power of the gas monitor, let it leave for about 10 minutes in a similar
environment to the operation location, and perform air calibration in fresh air before using it.

- 29 -

GX-8000

4 How to Use

4-7. Air calibration mode

NOTE Air calibration can be performed even when there is a gas alarm.
 If the air calibration fails, it displays [FAIL AIR CAL] and which sensor has
become faulty. Press the RESET switch to reset the fault alarm (calibration
failure). When the alarm is reset, the value before calibration is displayed.
If CH4 sensor is faulty

GX-8000- 30 -

4 How to Use

4-8. Display/setting mode

4-8. Display/setting modeThis mode allows you to change various displays and settings.
Every time the DISPLAY switch is pressed, various screens are displayed in turn.
LCD
Detection Mode

Display and Setting Mode
PEAK Value Display
Display the maximum
concentration detected during
measurement from power-on to
the present.

Full Scale Display/Alarm
Setpoint Display/Alarm Test
Display the full scale and alarm
setpoint values and check thealarm operations for the settings
displayed.

Full Scale Display/Alarm Setpoint
ENTER Display/Alarm Test
 P32

Pump ON/OFF Setting
Used to turn on/off the pump
operations.

Pump ON/OFF Setting
ENTER
 P33

ID Display/Selection
Display an ID if it has beenregistered in advance. Also used
to select an ID.

Log Data Display
Display concentration data
recorded to the manual memory.

ENTER

ID Display/Selection
 P34

ENTER

Log Data Display
 P35

To Detection Mode
- 31 -

GX-8000

4 How to Use

4-8. Display/setting mode

NOTE
The gas monitor automatically returns to the detection mode in about 20 seconds if the gas monitor is left
unoperated.
However, the gas monitor does not automatically return to the detection mode if the pump operation is set
to OFF.

<Full Scale Display/Alarm Setpoint Display/Alarm Test [ALARM-P]>
Display the full scale or alarm setpoint values and check the alarm operations for the settings displayed.
(1) Press the DISPLAY switch and select the full scale display / alarm setpoint display / alarm test from thedisplay/setting mode menu. The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to enter the alarm setpoint or other display.

NOTE
If you do not want to enter any display, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, the full scale and alarm setpoint menus, i.e., full scale display,first alarm setpoint display and second alarm setpoint display are displayed in turn.
Press either the ▲ or ▼ switch to select a setting that you want to check.
Select one of the following screens:

Full Scale Display

First Alarm Setpoint Display([WARNING])

Second Alarm Setpoint
Display ([ALARM])(4) Press the ENTER switch to perform alarm test. The alarm operation on this screen can be checked.
Press any switch to stop the alarm operation.
(5) Press the DISPLAY switch to exit the alarm setpoint display or alarm test. The display/setting modemenu is displayed again.
(6) After completion, press the DISPLAY switch several times until it returns to the detection mode.

GX-8000- 32 -

4 How to Use

4-8. Display/setting mode

<Pump ON/OFF Setting [PUMP OFF]>
Used to turn on/off the pump operations.

CAUTION While the pump operation is set to OFF, no gas detection is performed because no gas is drawn.
 The gas monitor does not automatically return to the detection mode if the pump operation is set
to OFF.
(1) Press the DISPLAY switch and select the pump ON/OFF setting from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to set the pump operation to ON or OFF.

NOTE
If you do not want to set the pump operation or ON or OFF, press the DISPLAY switch to return to thedisplay/setting mode menu.
(3) Every time the ENTER switch is pressed, the pump operation is turned ON or OFF.

Pump ON

Pump OFF

NOTE
While the pump operation is set to OFF, only the ENTER switch is enabled.
(4) To return to the detection mode, press the ENTER switch to set the pump operation to ON.
(5) After completion, press the DISPLAY switch several times until it returns to the detection mode.

- 33 -

GX-8000

4 How to Use

4-8. Display/setting mode

<ID Display/Selection [ID SELECT]>
Display an ID if it has been registered in advance. Also used to select an ID.
(1) Press the DISPLAY switch and select the ID display/selection from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to set or select an ID.

NOTE

 If you do not want to set or select an ID, press the DISPLAY switch to return to the display/setting
mode menu.
 On the gas monitor, either of the IDs from ST-ID000 to ST-ID255 has been registered, unlessotherwise specified.
 The data logger management program (option) is required to register or change an ID. Please contact
RIKEN KEIKI.
(3) Press either the ▲ or ▼ switch to select an ID.
Every time the ▲ or ▼ switch is pressed, the ID number increases or decreases (000 - 255).

(4) Press the ENTER switch.
(5) When [END] is displayed, the setting is completed.

The display/setting mode menu is displayed again.
(6) After completion, press the DISPLAY switch several times until it returns to the detection mode.

GX-8000- 34 -

4 How to Use

4-9. How to exit

<Log Data Display [REC.DATA]>
Display concentration data recorded to the manual memory.
(1) Press the DISPLAY switch and select the log data display from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to display the log data.

NOTE
If you do not want to display the log data, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, the log data menus are displayed in turn.
Press either the ▲ or ▼ switch to select log data that you want to check. The log data menu displays
the year, month, day, time, and memory number.

(4) Press the ENTER switch to display the selected log data.

(5) If you want to display other log data, press the ENTER switch to return to the log data menu. Repeat
the steps (3) - (5).
(6) After completion, press the DISPLAY switch to return to the detection mode.

4-9. How to exit
Make the gas monitor draw in fresh air. After the display returns to zero, keep the POWER/ENTER switch
pressed until the power is turned off.

NOTE
If the display is not zero when the power is turned off, a purge operation may be
performed for 30 seconds at the maximum to clean the inside of the gas monitor.

- 35 -

GX-8000

5 Operations and Functions

5-1. Gas alarm activation

5

Operations and Functions
5-1. Gas alarm activation
Gas alarm:

Triggered when the concentration of detected gas reaches or exceeds the alarm setpointvalue. <<Self-latching>>
Alarm display: Notified by blinking of a gas concentration value display, sounding of the buzzer, and lightingof the lamp.
Alarm types: First alarm (WARNING), second alarm (ALARM) and OVER alarm<List of Gas Alarms>
Alarm typeCombustible
gas
BuzzerAlarm lamp
LCD display

GX-8000

First alarm
10 %LEL

Second alarm
50 %LELOVER alarm
100 %LEL

Repeatedly sounds strong
and weak beeps at about
one second intervals:
Beep, beep
Repeatedly blinks at about
one second intervals.
Gas concentration and[WARNING] display blink.

Repeatedly sounds strong
and weak beeps at about
0.5 second intervals:
Blip, blip
Repeatedly blinks at about
0.5 second intervals.
Gas concentration and[ALARM] display blink.

Repeatedly sounds strong
and weak beeps at about
0.5 second intervals:
Blip, blip
Repeatedly blinks at about
0.5 second intervals.
Gas concentration and[OVER] display blink.

- 36 -

5 Operations and Functions

5-1. Gas alarm activation<Display Operation>
Gas Concentration Display
In a gas alarm, the gas concentration display and the alarm typedisplay blink.
In case of over the detection range (Over Scale), [∩∩∩] is displayedon the LCD.
Display example

NOTE
The alarm type of the OVER alarm is self-latching. Press the RESET switch to reset the alarm.
If the gas concentration is lower than the full scale at the pressing of the RESET switch, the alarm is reset
and the gas concentration display appears again. If it is over the full scale, an OVER alarm occurs again.
Alarm lamp
The alarm consists of two steps. Each of them is triggered when the respective alarm setpoint value isreached to or exceeded.
Buzzer
The alarm consists of two steps. Each of them sounds when the respective alarm setpoint value isreached to or exceeded.
"Alarm Pattern (H-HH)"
1 second interval
RESET

0.5 second interval

Concentration

Second alarm
setpoint
First alarm
setpoint

Time
Alarm lamp,
BuzzerWARNING
Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based on yourjudgment.

- 37 -

GX-8000

5 Operations and Functions

5-2. Fault alarm activation

5-2. Fault alarm activation
Fault alarm:
Triggered when an abnormality is detected in the gas monitor. <<Self-latching>>
Alarm display: Notified by display of error messages, sounding of the buzzer, and lighting of the lamp.
Alarm types: Low flow rate, sensor abnormality, battery voltage low, system abnormality, and calibration
failureDetermine the causes and take appropriate actions.
If the gas monitor has problems and is repeatedly malfunctioning, contact RIKEN KEIKI immediately.

<Display Operation>
LCD display

Display an error message.

Alarm lamp

Repeatedly blinks at about one second intervals.

BuzzerRepeatedly sounds intermittent beeps at about one second intervals:
Blip, beep, blip, beep

Display example

NOTE

 To reset a low flow rate alarm ([FAIL LOW FLOW]), remove the cause of the low flow rate, and thenpress the RESET switch.
 For information on malfunctions (error messages), see '8. Troubleshooting'.

5-3. Other functions<Calibration History/Various Trend/Event History Functions>
The gas monitor has history and trend functions. To use these functions, contact RIKEN KEIKI.

NOTE
The data logger management program (option) is required to use the history and trend functions. Pleasecontact RIKEN KEIKI.

GX-8000- 38 -

6 Maintenance

6-1. Maintenance intervals and items

6

MaintenanceThis is an important instrument for the purpose of safety.
To maintain the performance of the gas monitor and improve the reliability of safety, perform a regular
maintenance.

6-1. Maintenance intervals and items
 Daily maintenance: Perform maintenance before beginning to work.
 Monthly maintenance: Perform alarm test once a month.
 Regular maintenance: Perform a maintenance once or more for every six months to maintain theperformance as a safety unit.
Maintenance
item
Battery Level
Check
Concentration
Display
Check

Flow Rate
Check
Filter Check
Alarm Test

Span
Adjustment
Gas Alarm
Check

Maintenance content

Daily
Monthly
Regularmaintenance maintenance maintenanceCheck that the battery level is sufficient.
Make the gas monitor draw in fresh air andcheck that the concentration display value
is zero. When the reading is incorrect,
perform the zero adjustment (fresh air
adjustment) after ensuring that no othergases exist around it.
See the flow rate indicator to check for
abnormalities.
Check the dust filter for dust or clogging.
Check the alarm lamp and buzzer for
normal operation using the alarm test
function.
Perform the span adjustment by using thecalibration gas.
Check the gas alarm by using thecalibration gas.

- 39 -

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GX-8000

6 Maintenance

6-2. Gas calibration method<About Maintenance Services> We provide services on regular maintenance including span adjustment, other adjustments andmaintenance.
To make the calibration gas, dedicated tools, such as a gas cylinder of the specified concentration andgas sampling bag must be used.
Our qualified service engineers have expertise and knowledge on the dedicated tools used for services,along with other products. To maintain the safety operation of the gas monitor, please use ourmaintenance service.
 The followings are typical maintenance services. For more information, please contact RIKEN KEIKI.
Main Services
Battery Level
Check
Concentration
Display Check
Flow Rate Check

Filter Check
Alarm Test
Span Adjustment
Gas Alarm Check: Checks the battery level.
: Verifies that the concentration display value is zero by using the zero gas.
Performs the zero adjustment (fresh air adjustment) if the reading is incorrect.
: Checks the flow rate indicator to find abnormalities.
Checks the flow rate by using an external flow meter to verify the correctness of the flow rate
indicator on the gas monitor. If the flow rate is incorrect, performs the flow rate adjustment.
: Checks the dust filter for dust or clogging.
Replaces a dirty or clogged dust filter.
: Checks the alarm lamp and buzzer for normal operation using the alarm test function.
: Performs the span adjustment by using the calibration gas.
: Checks the gas alarm by using the calibration gas.
 Checks the alarm. (Checks the alarm activation when the alarm setpoint is reached.) Checks the delay time. (Checks time to delay until the alarm is triggered.) Checks the buzzer, lamp, and concentration display. (Check each activation of ALM1 and
ALM2.): Checks dust or damage on surface of the gas monitor, clean and repair such parts of the gas
monitor.
Replaces parts which are cracked or damaged.

Cleaning andRepair of Gas
Monitor(visual diagnosis)
Gas Monitor: Uses the keys to check the operation of functions and parameters.
Operation Check
Replacement of: Replaces consumable parts, such as a sensor, filter and pump.
Consumable Parts

6-2. Gas calibration method
Perform span adjustment of sensors using a calibration gas at least once every six months.
The span adjustment requires dedicated equipment and a calibration gas. Request RIKEN KEIKI for it.
If you perform the span adjustment for yourself, prepare these tools in advance and perform the adjustment
in accordance with the 'Maintenance Manual.'

CAUTION
Do not use a lighter gas to check the sensitivity of the gas monitor. A constituent of the lighter gas
may deteriorate the sensor performances.

GX-8000- 40 -

6 Maintenance

6-3. How to clean

6-3. How to clean
Clean the gas monitor if it becomes extremely dirty. The gas monitor must be turned off while cleaning it.
Use a waste cloth to remove dust. Do not use water or organic solvent for cleaning because they may cause
malfunctions.
Because an extremely large amount of dust inside the gas sampling hose may disturb the gas detection, it
must be cleaned with dry AIR, etc.

CAUTION
When cleaning the gas monitor, do not splash water over it or use organic solvents such as alcoholand benzene on it. The surface of the gas monitor may be discolored or damaged.

NOTE
When the gas monitor gets wet, water may remain in the buzzer sound opening or clearances. Drain
water as follows:(1) Wipe away moisture on the gas monitor thoroughly using a dry towel, cloth, etc.
(2) While holding the gas monitor firmly, shake it about ten times with the buzzer sound opening facing
downward.
(3) Wipe away moisture coming out from the inside thoroughly using a towel, cloth, etc.
(4) Place the gas monitor on a dry towel, cloth, etc. and let it stand at normal temperatures.

6-4. Parts replacement<Replacement of Consumables>
Sensor Replacement
The built-in sensors of the gas monitor have a validity period and must be replaced regularly (within two
years).
The sensor life has expired if, for example, the sensors cannot be calibrated in span adjustment, thereadings do not come back after fresh air adjustment, or the readings fluctuate. Contact RIKEN KEIKI. The
warranty period is one year for all the sensors.
Dust Filter Replacement Procedure
Because the dust filter may gradually get dirty or clogged over the time, it must be replaced regarding theoperating conditions. Check the dust filter, and then replace it as necessary.
The gas monitor has various built-in filters.
Gas sampling probe
Because the dust filter may gradually get dirty or clogged over time, it must be replaced regularly according
to the operating conditions.
It must be replaced especially when it shows a sign of water absorption, low flow rate or contamination①

Rotate the end of the probe
counterclockwise and remove it.
A round dust filter is contained here.
Check it for contamination or clogging.
Replace the dust filter if it is contaminatedheavily or clogged.

②③

Take out the filter and replace it with newone.
Reattach the filter case.

NOTE Use only the filters specified by RIKEN KEIKI.
- 41 -

GX-8000

6 Maintenance

6-4. Parts replacement<Replacement of Regular Replacement Parts>
List of recommended regular replacement parts
No.

Item

Maintenanceintervals

Replacement
intervals

Quantity(pieces per unit)

2 years

1 set

1

Rubber seal

2

Tube

6 months

3 - 8 years

1 set

3

Pump unit (RP-11)

6 months

1 - 2 years

1

4

Li-ion battery pack(BP-8000,BP-8000(1))(Li-ion battery unit only)





1

Remarks

About 500 cycles
of charging anddischarging

NOTE
The above replacement intervals are recommendation only. The intervals may change depending on theoperating conditions. These intervals do not mean the warranty periods either. The result of the regular
maintenance may determine when to replace the parts.
The operation of most of the periodical replacement parts must be checked after replacement by a qualified
service engineer.
For the stable operation of the gas monitor and safety, ask a qualified service engineer to take care of
replacement of the parts whose operation must be checked. Please contact RIKEN KEIKI.

GX-8000- 42 -

7 Storage and Disposal

7-1. Procedures to store the gas monitor or leave it for a long time7

Storage and Disposal
7-1. Procedures to store the gas monitor or leave it fora long time
The gas monitor must be stored under the following environmental conditions.
 In a dark place under the normal temperature and humidity away from direct sunlight In a place where gases, solvents or vapors are not present
Store the gas monitor in a shipping carton, if any, in which the product was delivered.
Store the gas monitor away from dust, etc. if the shipping carton is not available.

CAUTION
If the gas monitor is not used for a long time, turn on the power at least once every six months andcheck that the pump draws in air (about three minutes). The gas monitor, when not activated for along time, may cease to work because of hardening of the grease in the pump motor.

NOTE If the gas monitor with a Li-ion battery unit is not used for a long time, it is recommended to store it
after discharging the batteries until the battery level icon shows one battery mark or so. If the gas
monitor is stored with the batteries fully charged, the batteries get deteriorated more quickly and may
have shorter life.
 If the gas monitor with a dry battery unit is not used for a long time, store it after removing the batteries.
Battery leaks may result in fire or injury. If the gas monitor is not used for a short time, store it without
removing the batteries. While the power of the gas monitor is OFF, the sensor is energized at all times.
Therefore, it is necessary to store the gas monitor with the batteries in it.

7-2. Procedures to use the gas monitor again
CAUTION
When you use a stopped/stored gas monitor again, do not forget to perform a gas calibration. For
information on readjustment including gas calibration, please contact RIKEN KEIKI.

- 43 -

GX-8000

7 Storage and Disposal

7-3. Disposal of products

7-3. Disposal of products When the gas detector is disposed of, it must be treated properly as an industrial waste in accordancewith the local regulations.

WARNING Do not disassemble the electrochemical type sensor or galvanic cell type sensor because they
contain electrolyte. Electrolyte may cause severe skin burns if it contacts skin, while it may cause
blindness if it contacts eyes.
If electrolyte is adhered on you clothes, that part on your clothes is discolored or its material isdecomposed. If contact occurs, rinse the area immediately with a large quantity of water.
 Dispose of the batteries in accordance with procedure specified by the local authority.
 When disposing of the gas detector in EU member states, sort the batteries as specified. Handle theremoved batteries according to the classified refuse collection system and recycling system based on
the regulations of EU member states.
Contact RIKEN KEIKI for disposal.
Removing batteries
See '4-2. Preparation for start-up' and take out the batteries.
For BUL-8000(G), BUL-8000(G1)Model
BUL-8000(G)BUL-8000(G1)Type
Lithium ion battery

NOTE




BUL-8000(G), BUL-8000(G1) contains batteries.
Crossed-out recycle dustbin markThis symbol mark is indicated on the products which contain the batteries which fall under EU Battery
Directive 2006/66/EC. Such batteries need to be disposed of as specified by the latest Directive.
This symbol mark indicates that the batteries need to be separated from the ordinary waste and disposed ofappropriately.

GX-8000- 44 -

8 Troubleshooting

8

Troubleshooting
The troubleshooting does not explain the causes of all the malfunctions which occur on the gas monitor.
This simply helps to find the causes of malfunctions which frequently occur. If the gas monitor shows asymptom which is not explained in this manual, or still has malfunctions even though remedial actions aretaken, please contact RIKEN KEIKI.

<Abnormalities on Unit>
Symptoms
The power cannot
be turned on.

Abnormaloperations
Key operations are
disabled.

CausesThe battery level is too
low.

Actions
Li-ion battery unit: Charge the batteries in a
non-hazardous area.
Dry battery unit: Replace all the three dry batteries withnew ones in a non-hazardous area.
The power switch was
For power-on, keep the POWER switch pressed until a
not pressed long enough. beep is heard (about two seconds).
Improper installation of
Check whether the battery unit is properly attached tothe battery unit
the main unit.
Disturbances by sudden Turn off and restart the gas monitor.
surge noise, etc.
Disturbances by sudden In a non-hazardous area, remove the battery unit once,
surge noise, etc.
and reinstall the battery unit, and turn on the power toperform operations.
A circuit abnormality
occurred.
Request RIKEN KEIKI for repair.

Systemabnormalities[FAIL SYSTEM]
Systemabnormalities
Abnormalities of internal[FAIL SYSTEM]
Error No.000 ROM
Error No.010 Abnormalities of internal
RAM
Error No.021 Abnormalities of internal
FRAM
Error No.031 Abnormalities of internal
FLASH
SensorA sensor has failed.
abnormalities[FAIL SENSOR]
A low battery
The battery level is low.
voltage alarm isdisplayed.
[FAIL BATTERY]

Request RIKEN KEIKI for repair.

Request RIKEN KEIKI to replace the sensor.
Li-ion battery unit: Turn off the power and charge it in a
non-hazardous area.
Dry battery unit: Turn off the power and replace the drybatteries with new ones in a non-hazardous area.

- 45 -

GX-8000

8 Troubleshooting
Symptoms
A low flow rate
alarm is displayed.
[FAIL LOW FLOW]

Fresh airadjustment cannot
be performed.
[FAIL AIR CAL]
Clock
abnormalities[FAIL CLOCK]The batteries
cannot be charged.
(Li-ion battery unit
only)

CausesWater or oil, etc. wasdrawn in.
The gas sampling hose
is clogged.
The pump hasdeteriorated.
Fresh air is not suppliedaround the gas monitor.

Actions
Check the gas sampling hose for any damage or mark ofdrawn water or oil, etc.
Check the gas sampling hose for connections, clogging,twisting, etc.
Request RIKEN KEIKI to replace the pump.

Abnormalities of theinternal clock

Make a setting of Date/Time.
If such a symptom is observed repeatedly, the built-in
clock is seemingly malfunctioning. Thus, it must be
replaced. Please contact RIKEN KEIKI.
Connect the AC powered charger to the wall electric
outlet and jack properly.
Request RIKEN KEIKI for repair.

The charger is notconnected properly.
A charging circuit
abnormality occurred.
The batteries have been
fully charged.

Supply fresh air.

When fully charged batteries are charged again, thecharging indicator lamp does not go on.

<Abnormalities of Readings>
Symptoms
The reading rises(drops) and it
remains so.

Actions
Perform the zero adjustment (fresh air adjustment).
Disturbances by interference gases, such as solvents,
cannot be eliminated completely. For information on
actions, such as removal filter, please contact RIKEN
KEIKI.
Slow leakA very small amount of the gas to be detected may beleaking (slow leak). Because ignoring it may cause
dangers, take a remedial measure, i.e., taking actions thesame as those for the gas alarm.
Environmental changes Perform the zero adjustment (fresh air adjustment).
A gas alarm is
Presence of interference Disturbances by interference gases, such as solvents,
gas
cannot be eliminated completely. For information on
triggered despite
actions, such as removal filter, please contact RIKEN
of no gas leak and
KEIKI.
no otherabnormalities atDisturbance by noise
Turn off and restart the gas monitor.
the detection point.
If such a symptom is observed frequently, takeappropriate measures to eliminate the noise.
Slow response
Clogged dust filter
Replace the dust filter.
Bended or clogged
Fix the defective parts.
suction tube or exhausttube
Condensation is formed Fix the defective parts.
inside the suction tube.
Deteriorated sensor
Replace the sensor unit with a new one.
sensitivity
Span adjustment
Improper calibration gas Use the proper calibration gas.
concentration
impossible
Deteriorated sensor
Replace the sensor unit with a new one.
sensitivity

GX-8000

CausesDrifting of sensor output
Presence of interferencegas- 46 -

9 Product Specifications

9-1. List of specifications

9

Product Specifications
9-1. List of specifications<Japan Ex specification>
Detection principle
Gas to be detected
Detection range
Display resolution
Alarm setpoint

Accuracy of the reading
Response time
Alarm accuracy
Alarm delay time
Concentration display
Detection method
Suction flow rate
Displays
Buzzer sound volume
Gas alarm display
Gas alarm patternFault alarm/self
diagnosis
Fault alarm display
Fault alarm pattern
Transmission
specifications
FunctionsPower supply
Continuous operatingtime
Operating temperatures
Operating humidities
Operating pressure
Structure
Explosion-proof
structure
Explosion-proof class
External dimensions
WeightNew ceramic type (NC)
Combustible (HC, CH4, and H2) *1
0 – 100 %LEL
1 %LEL
10 %LEL (1st)
50 %LEL (2nd)
100 %LEL (OVER)
Within ±5 %LEL
90 % response: within 30 seconds
Within ±25 %30 seconds or less
LCD digital (seven-segment + Symbol + Bar meter)
Pump suction type0.75 L/min or more (Open flow rate)
Clock display, battery level display, pilot indicator, and pump driving indicator
95 dB(A) or higher (30 cm)
Lamp blinking, intermittent buzzer sounding, and gas concentration display blinking
Self-latching
System abnormalities, sensor abnormalities, battery voltage drop, calibration failure, and low flow rate
Lamp lighting, continuous buzzer sounding, and detail display
Self-latching
IrDA (for data logger)
LCD backlight, data logger, peak display, log data display, and pump stop
Dedicated dry battery unit <AA alkaline dry batteries  3> [BUD-8000(G),BUD-8000(G1)*2](Dedicated lithium ion battery unit [BUL-8000(G),BUL-8000(G1)*3] can also be used)
BUD-8000(G),BUD-8000(G1): About 6 hours (25 ºC, no alarm, and no lighting)
BUL-8000(G),BUL-8000(G1): About 12 hours (25 ºC, no alarm, no lighting, and battery fully charged)-20 ºC to 50 ºC
Below 95 %RH (Non-condensing)
Atmospheric pressure (80 kPa to 110 kPa)
Drip-proof and dust-proof performances (compliant to IP67 level)
Intrinsically safe explosion-proof structure

Ex ia ⅡC T4 X (Japan Ex)
Approx. 154 (W)  81 (H)  127 (D) mm (projection portions excluded)
Approx. 1.0 kg (BUD-8000(G), BUD-8000(G1) when in use)
Approx. 1.1 kg (BUL-8000(G), BUL-8000(G1) when in use)
*1 For JG (Japanese Government) type approval, the factory default setting is either CH4 or HC (specified in the order).
*2 In order to meet requirement about explosion-proof, use dedicated dry cell battery when using dry battery unit.
*3 JG (Japanese Government) type approval is only available for the rechargeable battery type (BUL).

- 47 -

GX-8000

9 Product Specifications

9-1. List of specifications<ATEX/IECEx specification>
Detection principle
Gas to be detected
Detection range
Display resolution
Alarm setpoint

Accuracy of the reading
Response time
Concentration display
Detection method
Suction flow rate
Displays
Buzzer sound volume
Gas alarm display
Gas alarm patternFault alarm/self
diagnosis
Fault alarm display
Fault alarm pattern
Transmission
specifications
FunctionsPower supply
Continuous operatingtime
Operating temperatures
Operating humidities
Operating pressure
Structure
Explosion-proof
structure
Explosion-proof class

External dimensions
Weight

GX-8000

New ceramic type (NC)
Combustible (HC, CH4, and H2)
0 – 100 %LEL
1 %LEL
10 %LEL (1st)
50 %LEL (2nd)
100 %LEL (OVER)
Within ±5 %LEL
90 % response: within 30 seconds
LCD digital (seven-segment + Symbol + Bar meter)
Pump suction type0.75 L/min or more (Open flow rate)
Clock display, battery level display, pilot indicator, and pump driving indicator
95 dB(A) or higher (30 cm)
Lamp blinking, intermittent buzzer sounding, and gas concentration display blinking
Self-latching
System abnormalities, sensor abnormalities, battery voltage drop, calibration failure, and low flow rate
Lamp lighting, continuous buzzer sounding, and detail display
Self-latching
IrDA (for data logger)
LCD backlight, data logger, peak display, log data display, and pump stop
Dedicated dry battery unit <AA alkaline dry batteries  3> [BUD-8000(G),BUD-8000(G1)](Dedicated lithium ion battery unit [BUL-8000(G),BUL-8000(G1)] can also be used)
BUD-8000(G),BUD-8000(G1): About 6 hours (25 ºC, no alarm, and no lighting)
BUL-8000(G),BUL-8000(G1): About 12 hours (25 ºC, no alarm, no lighting, and battery fully charged)-20 ºC to +50 ºC
Below 95 %RH (Non-condensing)
Atmospheric pressure (80 kPa to 110 kPa)
Drip-proof and dust-proof performances (compliant to IP67 level)
Intrinsically safe explosion-proof structure
ATEX
Ⅱ 1 G Ex ia ⅡC T4 Ga (without NC-6215) / Ⅱ 1 G Ex ia ⅡB T4 Ga (with NC-6215)
IECEx
Ex ia ⅡC T4 Ga (without NC-6215) / Ex ia ⅡB T4 Ga (with NC-6215)
Approx. 154 (W)  81 (H)  127 (D) mm (projection portions excluded)
Approx. 1.1 kg (BUL-8000(G), BUL-8000(G1) when in use)
Approx. 1.0 kg (BUD-8000(G), BUD-8000(G1) when in use)

- 48 -

9 Product Specifications

9-2. List of accessories

9-2. List of accessories
Standard
accessories







Dry battery unit (BUD-8000(G), BUD-8000(G1))
AA alkaline battery  3Shoulder strap
Gas sampling hose (1 m spiral)
Gas sampling probe

Optional
accessories




















Li-ion battery unit (BUL-8000(G), BUL-8000(G1))
AC powered charger
Waist strap
Waist strap fixing tool
Carrying case (leather)
Aluminum trunk case
Shipboard storage box
Sampling probe holder
Gas sampling hose (with float probe, 8 m)
Gas sampling hose 30 m with plummet
Filter tube
Filter tube fixing belt
Water trap
Relay tube
Set of gas bags
Span cans
Demand flow valve
Data logger management program- 49 -

GX-8000

10 Definition of Terms

10

Definition of Terms
LEL

GX-8000

An abbreviation for "Lower Explosion Limit."
LEL refers to the lowest concentration of a combustible gas in air capable ofcausing explosion when ignited.

- 50 -

GX-8000